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91.
92.
We demonstrate through the use of an in vitro assay involving the delayed addition of erythropoietin that human recombinant GM-CSF, cloned from a mature T cell line, Mo, clearly has burst-promoting activity (BPA) on peripheral blood erythroid progenitors at picomolar concentrations. Delay for up to 72 hours of the addition of erythropoietin to semi-solid methylcellulose cultures of concentrated peripheral blood progenitors minimizes or eliminates BPA-independent erythroid colony formation with little loss of BPA-dependent erythroid colony formation. This assay will prove useful in accurately detecting sources of BPA. 相似文献
93.
Acute allograft rejection in liver transplant recipients: lack of correlation with loss of hepatic artery diastolic flow 总被引:3,自引:0,他引:3
Eighty hepatic artery Doppler ultrasound (US) examinations performed in 49 patients after liver transplantation were retrospectively analyzed to determine if loss of diastolic flow correlated with pathologic evidence of acute allograft rejection. All 80 Doppler examinations were performed within 7 days of hepatic needle biopsy. Forty-three Doppler waveforms from 27 patients showed normal diastolic flow. Seventeen Doppler studies in 17 patients showed complete absence of diastolic flow. Review of biopsy results for each group showed no significant difference in the proportion of acute allograft rejection present (42% for the normal group and 46% for the group lacking diastolic flow). The data from 53 US and biopsy examinations performed 2 days apart in 37 patients confirmed the lack of correlation between absent hepatic artery diastolic blood flow and rejection. The authors conclude that the loss of hepatic artery diastolic flow has no apparent clinical application for the diagnosis of acute hepatic allograft rejection. 相似文献
94.
目的:评价纺织工作环境及其噪声对纺织女工心理健康的影响,为有关部门制定卫生标准和防护措施提供科学依据。
方法:调查于2006-02/04进行,选取成都市某织布厂接触噪声高于85dB(A)的女工341名作观察组,另选取同厂接触噪声强度低于85dB(A)的女工154名作对照组,检测两组作业环境的噪声强度、风速、气温、气湿,并了解两组受试者的一般情况,采用SCL-90症状自评量表评价调查对象的心理健康状况,包括躯体不适、强迫症状、人际关系敏感、抑郁、焦虑、敌对、恐怖、偏执和精神病性9项因子,得分越高症状越重。
结果:495名受试者的资料进入结果分析。①两组作业环境检测,除观察组接触的噪声强度超过国家噪声卫生限值[85dB(A)]外,两组的其余各项指标均符合国家卫生标准,并且其一般情况的构成相似。②观察组SCL-90量表的9项因子分、总均分、阳性项目数以及阳性症状均分均高于对照组(P〈0.05),躯体不适和强迫症状两项因子分≥3分的阳性检出率明显高于对照组(P〈0.05)。③观察组各个工龄组SCL-90的9项因子分、总均分和阳性项目数中,除躯体不适和敌对因子以外,其余指标均以1-年工龄组为最高(P〈0.05)。
结论:高强度的纺织噪声对女工心理健康有一定的影响,其中对1-年工龄组的影响最明显。建议采取积极有效的措施,以保护纺织女工的心理健康。 相似文献
95.
Post-cimetidine Surveillance for up to Ten Years: Incidence of Carcinoma of the Stomach and Oesophagus 总被引:1,自引:0,他引:1
COLIN-JONES DG; LANGMAN MJS; LAWSON DH; LOGAN RFA; PATERSON KR; VESSEY MP 《QJM : monthly journal of the Association of Physicians》1991,78(1):13-19
The long-term effects of cimetidine on the occurrence of gastricand oesophageal cancer were assessed in a prospective cohortstudy of 9928 patients who had been prescribed cimetidine. Theywere first identified between 1978 and 1980, and cancer registrationsand deaths were identified among them over a period of up to10 years. One hundred and eleven cancers were identified afterthe start of cimetidine treatment: 71 were adenocarcinomas ofthe stomach, 27 were carcinomas of the cardia and/or oesophagus(22 adenocarcinomas, five unknown histology) and the remaining13 tumours were squamous cell cancers of the oesophagus. Onlysix patients presented with early gastric cancers. Over a periodof eight years the ratio of observed to expected (O/E) gastriccancer deaths has fallen from 10.7 (p<0.001) to 1.2 (NS).The O/E ratio of oesophageal cancer deaths also fell over thefirst six years of study, from 5.4 (p<0.01) to 1.4 (NS) butit has risen slightly in years 7 and 8 to 3.7 (p<0.05). Thesefindings do not suggest that there is an increased risk of developingoesophageal or gastric cancer from cimetidine treatment, andare generally consistent with cimetidine being used inadvertentlyto treat the early symptoms of gastric and oesophageal cancer.The slight rise in oesophageal cancer deaths in years 7 and8 was unexpected and will be the subject of further observation. 相似文献
96.
N Mamode FRCS K Mercer MB Ch B DG Gilmour FRCS 《International journal of clinical practice》1996,50(7):410-410
SUMMARY Six days after admission to hospital with Salmonella gastroenteritis, this patient presented with a critically ischaemic leg, having developed an iliac occlusion, and a subcutaneous Salmonella abscess in the anterior compartment of the leg. Critical limb ischaemia and abscess formation can be added to infective aortic aneurysm as vascular complications of Salmonella gastroenteritis. 相似文献
97.
Recombinant human interleukin-1 receptor antagonist in the treatment of steroid-resistant graft-versus-host disease 总被引:11,自引:1,他引:11
Antin JH; Weinstein HJ; Guinan EC; McCarthy P; Bierer BE; Gilliland DG; Parsons SK; Ballen KK; Rimm IJ; Falzarano G 《Blood》1994,84(4):1342-1348
Acute graft-versus-host disease (GVHD) that is resistant to therapy is a highly lethal complication of marrow transplantation. Inflammatory cytokines such as interleukin-1 (IL-1) may be critical mediators of this process. If so, specific inhibition of IL-1 activity with recombinant human IL-1 receptor antagonist (IL-1Ra), a naturally occurring competitive inhibitor of IL-1, may ameliorate acute GVHD. We performed an open-label, phase I/II trial to evaluate the safety and efficacy of IL-1Ra in 17 patients with steroid-resistant GVHD. The IL- 1Ra was administered as a 24-hour continuous infusion over 7 days. The dose was escalated in cohorts of patients from 400 to 3,200 mg/d. Acute GVHD was evaluated in each affected organ and as an overall grade. Stage-specific improvement of acute GVHD occurred in the skin (8 of 14, 57%), gut (9 of 11, 82%), and liver (2 of 11, 18%). Overall, acute GVHD improved by at least one grade in 10 of 16 (63%) patients. Response to therapy was associated with a reduction of tumor necrosis factor-alpha (TNF-alpha) mRNA levels in blood mononuclear cells (P = .001). The only toxicity attributable to IL-1Ra was reversible transaminase elevation in two patients. Inhibition of IL-1 activity with IL-1Ra is safe and has demonstrable efficacy in acute GVHD that failed to respond to conventional treatment. These data provide further evidence that IL-1 is a mediator of GVHD. 相似文献
98.
Interleukin-3 expression by activated T cells involves an inducible, T- cell-specific factor and an octamer binding protein 总被引:2,自引:0,他引:2
Interleukin-3 (IL-3) is exclusively expressed by activated T and natural killer cells, a function that is tightly controlled both in a lineage-specific and in a stimulation-dependent manner. We have investigated the protein binding characteristics and functional importance of the ACT-1-activating region of the IL-3 promoter. This region binds an inducible, T-cell-specific factor over its 5' end, a site that is necessary for the expression of IL-3 in the absence of other upstream elements. Over its 3' end, it binds a factor that is ubiquitously and constitutively expressed. This factor is Oct-1 or an immunologically related octamer-binding protein, and it plays a role in coordinating the activity of several regulatory elements. These characteristics make the ACT-1 site analogous to the activating ARRE-1 site in the IL-2 promoter. Furthermore, and despite a lack of sequence homology, the promoters of IL-3 and IL-2 share an organizational pattern of regulatory elements that is likely to be important for the T- cell-specific expression of these genes. 相似文献
99.
Custom-made monoclonal anti-idiotype antibodies (anti-Id MoAbs) have been tested as a treatment modality in 34 non-Hodgkin's lymphoma (NHL) patients. Partial or complete tumor remissions have been induced with this treatment in 68% of these patients. One mechanism by which anti- idiotype antibodies may have induced these tumor responses is via a direct antiproliferative effect on the tumor cells, resulting in apoptosis. Primary NHL cells do not proliferate well enough in vitro to test this hypothesis directly. Therefore, we studied the effect of anti- idiotype antibodies on signal transduction through the surface Ig receptor as measured by the induction of cellular protein tyrosine phosphorylation. To assess whether bcl-2 protein could protect lymphoma cells from death induced by anti-Id MoAb, we also measured the level of bcl-2 protein in the same tumor cells. We found a strong correlation between the ability of an anti-Id MoAb to induce an increase in tyrosine phosphorylation in vitro and its ability to induce a tumor regression in the patient. By contrast, the level of bcl-2 expressed by the tumor cells was not correlated with clinical response to anti-Id MoAb treatment. 相似文献
100.
Production of granulocyte-macrophage colony-stimulating factor by primary cultures of unstimulated rat microvascular endothelial cells 总被引:1,自引:0,他引:1
Small vessel (microvascular) endothelial cells are in close contact with hematopoietic progenitor cells in the bone marrow and therefore may have an important role in hematopoiesis. Although other studies have shown that endothelial cells produce various colony-stimulating factors (CSFs), these studies examined large vessel endothelial cells, which are different in many respects from microvascular endothelial cells and which do not contact cells in the bone marrow. We show in this study that primary cultures of unstimulated rat fat capillary endothelial cells grown in serum-free medium produce a substantial amount of granulocyte-macrophage CSF (GM-CSF). The medium conditioned by these cells stimulated proliferation of two different lines of GM- CSF-responsive cells--PT-18 mast cells and FDC-P1 cells--and supported the growth of cells of the granulocyte and macrophage lines in cultures of rat bone marrow cells. The factor responsible for this activity had physical properties consistent with those of GM-CSF, namely, a similar apparent mol wt by gel filtration, resistance to repeated freeze-thaws, resistance to boiling for ten minutes but not for 30 minutes, and resistance to heating to 56 degrees C for one hour. The factor causing target cell stimulation was not B cell-stimulating factor-1 (BSF-1, or IL 4), since it failed to stimulate a BSF-1-responsive cell line HT2- JH, and target cells (PT-18) did not respond appreciably to recombinant BSF-1. Northern blot analysis of mRNA from rat fat capillary endothelial cells showed high levels of expression of GM-CSF, confirming that this factor is produced by microvascular endothelial cells. This is the first report of CSF production by unstimulated microvascular endothelial cells, demonstrating that these ubiquitous cells are capable of producing sizable amounts of at least one growth factor for hematopoietic progenitor cells. 相似文献